Quantitative Aptitude - Arithmetic Ability Questions

Find x, if 5x-6+5x+6 = 6

If ab+ba = -1, then the value of a2b-b2a is

If x – (1/x) = 3, then what is the value of (2x4 + 3x3 + 13x2 – 3x + 2) / (3x4 + 3)?

A thief is stopped by a policeman from a distance of 150 metres. When the policeman starts the chase, the thief also starts running. Assuming the speed of the thief as 7 km/hr and that of policeman as 9 km/hr, how far the thief would have run, before he is over- taken by the policeman?

The radius of a sphere and hemisphere are same. The ratio of their total surface area is

12 men complete a work in 9 days. After they have worked for 6 days, 6 more men join them. How many days will they take to complete the remaining work?

If 2r = h + r2+h2, then the ratio of r:h is

If x2+1x2 = 98, then x3+1x3 = ?